Scientists have found the part of our brains that makes us expect the worst

Good news for real-life grumpy cats: if you find yourself expecting the worst and struggle to get motivated, the problem isn’t your personality. You probably just have a hyperactive habenula.

British scientists now believe that this small (half the size of a pea) part of the brain is responsible for our negative predications and worse-case-scenario thinking. And the more bad experiences someone has had, the more active it’s likely to be.

In a small-scale study, researchers from University College London asked 23 participants to lie in an MRI scanner while they were shown either pictures showing painful electric shocks or pictures that depicted winning money.

The first category of pictures activated the habenula, while the second type calmed it down. The scientists found that the strength of the reaction seemed to depend on past experience, so that after someone had seen a lot of negatively-associated images that was what they started to expect. By tracking brain activity before showing a new picture, the scientists could tell whether someone was expecting a bad or a good picture.

Periodically, the participants were asked to hit a buzzer to signal that they were still paying attention to the test. People tended to respond more slowly when their brain showed that they anticipated a negative picture next, even though their response had no effect on the outcome. The more slowly they reacted, the more strongly their habenula reacted to the shock images.

It’s not surprising that people expecting the worst would cause them to feel fearful and unmotivated, but this is the first time scientists have observed this process in humans. Previous studies in animals had showed that habenula activity increased when something unpleasant happened to them (poor things), and scientists linked this to a decrease in dopamine, a hormone that makes people more gung-ho (yep, that is the medical term).

It seems that the same could be true for people, meaning larger trials are needed to see if the habenula could be the key to developing more effective treatment for depression – and to getting the rest of us to stop planning for the worst, and start hoping for the best.

Staff Writer Diane is especially interested in high-tech medical advances, weird and interesting uses of science, new gadgets, and the intersection of tech and lifestyle. When not working, she reads the internet, listens to podcasts, watches American TV, and thinks about leaving the house.